Interactive assistant modules are software processes installed on computing devices such as smart phones, tablets, vehicle navigation systems, standalone voice-activated products, and smart watches to provide user-friendly interfaces for users to issue natural language commands and/or engage in dialog with the interactive assistant module, gestures, facial expressions, etc. Users often issue natural language commands using their voices, but interactive assistant modules may respond to other modalities as well, such as various forms of textual input. Grammars employed by existing interactive assistant modules tend to be developed using so-called “prescriptive linguistic” approaches, which are concerned with how a language should be used, rather than how it is actually used. Consequently, existing grammars only provide users with limited flexibility in issuing voice-based commands. If a user's voice command deviates too much from existing grammars—e.g., because the user issues a so-called “long tail” voice command—the voice command may not be recognized. It may be possible to create associations between arbitrary, voice-based triggers (i.e., voice-based triggers) and responsive actions, but this may require users to manually create such associations, e.g., using a graphical user interface or by engaging in extensive dialog with an interactive assistant module. Moreover, slight deviation between an issued voice command and a voice-based trigger may lead to the voice-based trigger not being recognized.